This invention relates to buildings and construction, and more particularly to controlling moisture to reduce the likelihood of mold growth and moisture damage.
Mold and mildew problems in buildings are becoming more common, and can lead to substantial remediation efforts, with associated costs or litigation.
In building construction, whether commercial or single or multiple family residential, problems can arise if a particular level of moisture remains in walls at the time the walls are sealed. During construction, these buildings are typically wet, either from rain/snow or from wet construction materials being used, for example, wet wood, or materials that are applied in a wet state and then need to dry. Mold will typically grow in wood or other construction material when there is sufficient moisture present, for example, above 20% moisture in Douglas fir.
Mold spores can grow if sufficient moisture is sealed into construction material and there is an available food source. Should mold develop, it is often detected immediately, or sometimes such detection is delayed. In some cases, it is never detected.
Mold remediation, such as removal and prevention of future growth, is costly and time consuming. The existence of mold in a construction project can cause public relations issues, wherein the builder or project developer can be equated with the bad publicity related to the mold issues. Still further, legal issues can arise, related to the costs and delay of remediation, alleged health issues from occupants of the affected buildings, and contractual disputes arising over purchase or lease of the affected property, as a purchaser might wish to cancel a property transaction based on the mold issues.
Apart from mold issues, the presence of moisture alone can also lead to damage to structures and materials, resulting in costly remediation with corresponding issues to those noted hereinabove with respect to mold.
Financing and monetary requirements demand that structures be built as quickly as possible, to minimize the duration of construction financing, for example, and to increase construction-related revenue. Such time constraints result in framing being covered up as quickly as possible. These time constraints do not allow a builder to have a partially completed structure sit for weeks to allow any moisture in the construction materials to naturally reach equilibrium with its environment, and this increases the likelihood that wet materials may be sealed up, leading to a higher likelihood of mold growth or moisture damage occurring. Depending on climate factors, the business cycle of construction may not allow sufficient time for waiting for the natural drying process.
In particular in new construction, building practices resulting in an energy efficient structure may severely restrict airflow between the interior and exterior of a structure, resulting in trapping of moisture inside the structure. This can increase the likelihood of mold or moisture problems in structures today.
Heretofore, the issue of mold has been addressed as an afterthought in reactive fashion, only being tackled when mold appears, advising cleaning up mold quickly when it appears, for example.